Tibbetts Creek is a relatively short creek (4.3 miles long) that originates on Squak Mountain at an elevation of 1,080 feet. The stream flows through a steep headwater area, then in midcourse opens up to a broad flood plain that empties into Lake Sammamish. Though not a tributary to Issaquah Creek, it shares a common floodplain with the mainstem during large flood events.
Efforts to restore the damaged creek have been underway for more than ten years. In the summer of 2002, more than 10,000 cubic yards of mine tailings were excavated from where the debris had been dumped into a gully along Tibbetts Creek by mine operators. Prior to excavation, heavy rains would wash large quantities of the tailings into the creek. The sediment clogged channels, which impeded salmon and trout migration and contributed to downstream flooding. The mine closed in the 1950s (Seattle Times, November 22, 2002).
A site, roughly 5-acres in size, was replanted in 2002 on part of a 400-acre parcel between Cougar and Squak mountains deeded to Issaquah in May by the Talus developers. The transfer preserves valuable wildlife habitat, creating a mile-wide swath of public land that connects the Cougar Mountain and Squak Mountain parks. The restoration is a joint effort by Issaquah, local environmental groups, and the developers of Talus. Its purpose is to restore fish habitat, reduce flooding, and eliminate a significant source of phosphorus
About 1,800 feet of new stream channel, complete with standing snags and strategically placed logs, has been built on Rowley Enterprises property south of Interstate-90. Rowley Enterprises has committed $1.2 million to the restoration project. The process also included the Muckleshoot Tribe; the City of Issaquah; the volunteer Friends of the Issaquah Fish Hatchery, and the State Departments of Transportation, Parks, and Fish and Wildlife.
Total land use in the basin dominated by forest (mostly mixed forest) and developed land. Agriculture and other (barren and grassland) make up a very small portion of total land use (1% combined). Scrub and wetlands also comprise a small, albeit slightly larger, percent of land use. See Table 1 below for more details on land use.
Table 1. Total land use in the basin
| |
Agriculture |
Developed |
Forest |
Scrub |
Wetlands |
Other |
| Total |
<1% |
30% |
67% |
2% |
<1% |
<1% |
